An approach to force and position control of robot manipulators

Abstract

An approach is proposed to simultaneously control the contact forces exerted on a constraint surface and the position of the end-effector, both in the presence of frictional forces on the constraint surface. The approach, using a novel formulation of the dynamics model, is based on a linear state feedback. A feedforward and PI (proportional-integral) feedback control strategy is proposed along with a design procedure. Using the proposed control method the trajectory following problem is solved and the closed-loop system is shown to be asymptotically stable. Numerical examples of a two-link robot moving along a constraint surface are presented for illustration.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>